The Echinoid Directory

Infulaster Desor, 1858, p. 347 [ex. Hagenow MS]

Diagnostic Features
  • Test longer than wide, with pronounced apical peak in profile.
  • Sharp anterior sulcus runs from apex to peristome; largely vertical.
  • Apical disc elongate with four gonopores. Anterior genital plates fused.
  • Paired ambulacra flush, with small circumflexed pore-pairs; apetaloid.
  • Peristome circular and facing obliquely towards anterior groove.
  • Plastron uniserial, with two or three single plates following the labrum.
  • Plastron plating never disjunct.
  • Periproct supramarginal, on steeply sloping posterior face.
  • Enlarged primary tubercles in periapical region and bordering frontal groove.
  • Marginal fasciole present around posterior of test.
Distribution
Upper Cretaceous (Turonian to Coniacian); western Europe.
Name gender masculine
Type
Cardiaster hagenowi d\'Orbigny, 1853 (=Spatangus excentricus Woodward, 1833), by original designation.
Species Included
  • I. excentricus (Woodward, 1833); Upper Turonian to Coniacian, western Europe.
  • I. navicularis Dieni & Kroh, 2014; Coniacian, Sardinia.
  • I. praecursor Smith & Wright, 2003; Turonian, UK.
  • I. tuberculatus Valette, 1913; Turonian-Coniacian, western Europe.
Classification and/or Status

Holasteroida, Cardiasteridae.

Paraphyletic, by exclusion of Hagenowia.

Remarks

A detailed account of the group and its possible mode of life is given by Gale & Smith (1982). This taxon differs from Hagenowia in having a less pronounced and much less acute apical rostrum and a continuous rather than disjunct plastron. It is distinguished from Cardiaster by having a much more anterior apical disc and uniserial plating on the plastron; in Cardiaster the plates of the plastron may become uniserial, but with successive plates triangular and offset to left and right, whereas in Infulaster the first three plates are linearly arranged.

Smith, A. B. & Wright, C. W. 2003. British Cretaceous echinoids. Part 7, Atelostomata, 1. Holasteroida. Palaeontographical Society Monographs, London. Pp. 440-568, pls 139-182.

Gale, A. S. & Smith, A. B. 1982. The palaeobiology of the Cretaceous irregular echinoids Infulaster and Hagenowia. Palaeontology 25, 11-42.

Kroh, A. & Wagreich, M. 2007. Infulaster (Echinodermata: Echinoidea) from the Turonian of the Northern Calcareous Alps. Austrian Journal of Earth Sciences 100, 154-161.

Dieni, I. & Kroh, A. 2014. Boreal echinoids from the Tethys Realm: Infulaster and Hagenowia from the Upper Cretaceous of eastern Sardinia (Italy). Journal of Systematic Palaeontology